Australia's only active volcano cluster has erupted, with lava flowing from Big Ben on remote islands in the Southern Ocean. The two volcanoes on Heard Island and McDonald Islands were seen erupting by scientists on a research mission to map the seafloor around the little known area.

The team, led by researchers from the University of Tasmania's Institute for Marine and Antarctic Studies (IMAS) had been out at sea for more than two weeks when they arrived at the islands, which are more than 4,000km south-west of Perth. Very little is known about the islands and even less is known of the two volcanoes there.

Eruptions have only ever been recorded through satellite images and seen by just a few people. In total, the volcanoes have erupted three times in the past 15 years. However, shortly after arriving at the site, Mawson Peak (the highest point on the volcano named Big Ben) started erupting, with lava flowing down it's side. Vapour was also seen coming from the volcano on the McDonald Islands.

Jodi Fox, a scientist on the mission, said: "I'm doing my PhD on Heard Island volcanism, and to see lava emanating from Mawson Peak and flowing down the flank of Big Ben over a glacier has been incredible. Given persistent cloud cover and generally foul weather, I didn't think we'd even see Mawson Peak on this voyage."

Mike Coffin, chief scientist on the mission, said: "Seeing vapour emanating from both of Australia's active volcanoes and witnessing an eruption at Mawson Peak have been an amazing coda to this week's submarine research. We have 10 excited geoscientists aboard Investigator, and our enthusiasm has spread to our 50 shipmates".